• 文献标题:   Magnetic Interactions in Substitutional Core-Doped Graphene Nanoribbons
  • 文献类型:   Article
  • 作  者:   WEN ECH, JACOBSE PH, JIANG JW, WANG ZY, MCCURDY RD, LOUIE SG, CROMMIE MF, FISCHER FR
  • 作者关键词:  
  • 出版物名称:   JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
  • ISSN:   0002-7863 EI 1520-5126
  • 通讯作者地址:  
  • 被引频次:   5
  • DOI:   10.1021/jacs.2c04432 EA JUL 2022
  • 出版年:   2022

▎ 摘  要

The design of a spin imbalance within the crystallographic unit cell of bottom-up engineered 1D graphene nanoribbons (GNRs) gives rise to nonzero magnetic moments within each cell. Here, we demonstrate the bottom-up assembly and spectroscopic characterization of a one-dimensional Kondo spin chain formed by a chevron-type GNR (cGNR) physisorbed on Au(111). Substitutional nitrogen core doping introduces a pair of low-lying occupied states per monomer within the semiconducting gap of cGNRs. Charging resulting from e the interaction with the gold substrate quenches one electronic state for each monomer, leaving behind a ID chain of radical cations commensurate with the unit cell of the ribbon. Scanning tunneling microscopy (STM) and spectroscopy (STS) reveal the signature of a Kondo resonance emerging from the interaction of S = 1/2 spin centers in each monomer core with itinerant electrons in the Au substrate. STM tip lift-off experiments locally reduce the effective screening of the unpaired radical cation being lifted, revealing a robust exchange coupling between neighboring spin centers. First-principles DFT-LSDA calculations support the presence of magnetic moments in the core of this GNR when it is placed on Au.